Gaming machines, such as slot machines, video poker machines and the like, have been a cornerstone of the gaming industry for several years. Generally, the popularity of such machines with players is dependent on the likelihood (or perceived likelihood) of winning money at the machine and the intrinsic entertainment value of the machine relative to other available gaming options. Where the available gaming options include a number of competing machines and the expectation of winning at each machine is roughly the same (or believed to be the same), players are likely to be attracted to the most entertaining and exciting machines. Shrewd operators consequently strive to employ the most entertaining and exciting machines, features, and enhancements available because such machines attract frequent play and hence increase profitability to the operator. Therefore, there is a continuing need for gaming machine manufacturers to continuously develop new games and improved gaming enhancements that will attract frequent play through enhanced entertainment value to the player.
One concept that has been successfully employed to enhance the entertainment value of a game is the concept of a “secondary” or “bonus” game that may be played in conjunction with a “basic” game. The bonus game may comprise any type of game, either similar to or completely different from the basic game, which is entered upon the occurrence of a selected event or outcome in the basic game. Generally, bonus games provide a greater expectation of winning than the basic game and may also be accompanied with more attractive or unusual video displays and/or audio. Bonus games may additionally award players with “progressive jackpot” awards that are funded, at least in part, by a percentage of coin-in from the gaming machine or a plurality of participating gaming machines. Because the bonus game concept offers tremendous advantages in player appeal and excitement relative to other known games, and because such games are attractive to both players and operators, there is a continuing need to develop gaming systems with new types of bonus games to satisfy the demands of players and operators.
Traditionally, gaming machines display randomly selected outcomes of symbols and award players for winning combinations of symbols in accordance with a pay table. Other gaming machines have employed “clumping” of symbols, where groups or “clumps” of the same symbol appear adjacent to one another on vertical reels. The clumped symbols increase the likelihood of achieving a winning outcome and corresponding award. One problem that arises is that given the increased likelihood of a winning outcome, the clumped symbols often correspond to relatively lower awards on the pay table. Another problem exists in that if symbols corresponding to higher awards are clumped, the frequency of the occurrence of such clumped symbols is reduced to maintain a predetermined level or range of payout percentage. In other words, given the increased likelihood of greater awards, the frequency of such a result is reduced, thereby reducing enjoyment of the wagering game. Yet another problem that arises is that regardless of whether clumped symbols are used or not, as the randomly selected outcome is revealed to the player, enjoyment and anticipation are brief given the immediate perception of whether or not a winning outcome has been achieved, and if so, which symbols are involved in the winning outcome is and how it is awarded. The present invention is directed to solving these and other problems.